JPH0397828A - Production of rocker arm - Google Patents
Production of rocker armInfo
- Publication number
- JPH0397828A JPH0397828A JP1231732A JP23173289A JPH0397828A JP H0397828 A JPH0397828 A JP H0397828A JP 1231732 A JP1231732 A JP 1231732A JP 23173289 A JP23173289 A JP 23173289A JP H0397828 A JPH0397828 A JP H0397828A
- Authority
- JP
- Japan
- Prior art keywords
- rocker arm
- cast iron
- carbide
- treatment agent
- molten metal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 21
- 229910001018 Cast iron Inorganic materials 0.000 claims abstract description 13
- 238000005266 casting Methods 0.000 claims abstract description 8
- 229910014458 Ca-Si Inorganic materials 0.000 claims abstract description 7
- 239000011651 chromium Substances 0.000 claims description 14
- 229910052751 metal Inorganic materials 0.000 claims description 13
- 239000002184 metal Substances 0.000 claims description 13
- 229910052804 chromium Inorganic materials 0.000 claims description 11
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 9
- 229910052748 manganese Inorganic materials 0.000 claims description 3
- 229910052684 Cerium Inorganic materials 0.000 claims description 2
- 229910052782 aluminium Inorganic materials 0.000 claims description 2
- 229910052749 magnesium Inorganic materials 0.000 claims description 2
- 229910052726 zirconium Inorganic materials 0.000 claims description 2
- 229910017060 Fe Cr Inorganic materials 0.000 abstract description 7
- 229910002544 Fe-Cr Inorganic materials 0.000 abstract description 7
- UPHIPHFJVNKLMR-UHFFFAOYSA-N chromium iron Chemical compound [Cr].[Fe] UPHIPHFJVNKLMR-UHFFFAOYSA-N 0.000 abstract description 7
- 230000013011 mating Effects 0.000 abstract description 7
- 239000000463 material Substances 0.000 abstract description 4
- 230000001376 precipitating effect Effects 0.000 abstract 2
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 230000000694 effects Effects 0.000 description 9
- 230000000052 comparative effect Effects 0.000 description 6
- 239000002131 composite material Substances 0.000 description 4
- 150000001247 metal acetylides Chemical class 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 2
- 238000005469 granulation Methods 0.000 description 2
- 230000003179 granulation Effects 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000002344 surface layer Substances 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- 238000010191 image analysis Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000011081 inoculation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000004579 marble Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910001562 pearlite Inorganic materials 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/08—Making cast-iron alloys
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Valve-Gear Or Valve Arrangements (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
Abstract
Description
【発明の詳細な説明】
[産業上の利用分野]
本発明は自動車用内燃機関の動弁機構に使用される高ク
ロム鋳鉄製ロッカーアームの製造方法の改良に関するも
のである.
[従来の技術]
高クロム鋳鉄を用いてWd摩耗性の良好なロッカーアー
ムを一体に鋳造することは,特開昭63−303030
号に開示されている.高クロム鋳鉄製ロッカーアームの
耐摩耗性は、高硬度の(Fe,Cr)?C3等の炭化物
によるものである.
[発明が解決しようとする課N]
高硬度のFe−Cr複合化合物は指向性凝固により表層
に向けて針状に析出する傾向を有する.この表層を向い
た針状炭化物が相手摺動部材を摩粍させるという問題が
あった.タンクステンを添加すると,Fe−Cr複合炭
化物を粒状(球体)化させることができるが、この場合
、多量の添加(lO%以上)は、コスト高となり、また
高硬度なタングステン複合炭化物が相手材を摩耗させる
ため,問題の解決にはならなかった.
本発明は上記問題を解決するためになされたものであり
、その目的とするところは相手材を摩耗させない高クロ
ム鋳鉄製ロッカーアームを製造することにある.
[課題を解決するための千段」
本願の発明者は高クロム鋳鉄の溶湯処理剤がFe−Cr
複合炭化物の粒状化に有効なことを見出して研究を進め
,前記目的を達威することができた.
本発明が採用した手段は、高クロム鋳鉄によりロー2カ
ーアームを一体鋳造する方法において、Ca−Si系処
理剤を溶湯に対して0.3〜0.6%添加することにあ
る.
Cr−St系処理剤はCaを約30%、Siを約60%
、不純物を約10%含むが、この処理剤に対してBa.
Sr.Mg,Zr,Ce.Mn.AfLの1種又は2種
以上を0.5〜5%重量%添加してもよい.高クロム鋳
鉄はCrをlO%以上含むものであるが,好ましいもの
としては化学組或が重量%で、C:2.5〜3.7%、
Si:1.0〜2.0%、Mn:0.5〜1.0%、C
r:L5 〜20%、 Ni:0.3 〜0.7%、
P:0.3%以下、S:1.0%以下の範囲であり、必
要に応じて、W.Mo、■、Nb.Ta.Ti,Bの中
の1種又は2種以上を合計で3〜10%含み、残部がF
e及び不可避的不純物よりなるものを挙げることができ
る,
[作用]
Ca−Si系処理剤は溶湯の脱酸処理剤として用いられ
るが、粒状化を目的として使用する場合には、溶湯に対
して処理剤が0.3%未満では炭化物抑制効果が本十分
であり、発明の目的を達威することはできない.又、逆
に、処理剤が0.6%を越えても,効果に変化はなくコ
スト高を招くだけであるから、溶湯に対する処理剤は0
.3〜0.6重量%とする.さらに、Ca−Si系処理
剤は反応が穏やかなため、作業性が良好で歩留も高いと
いう長所を持つ.
B a,S r,Mg.Z r.C e.Mn、Alは
、接種効果消失作用(フェイディング)を遅延させる作
用を有し,酸素との親和力も強〈、顕著な脱酸作用があ
るから,Ca−St系処理剤に添加すると、Fe−Cr
炭化物の粒状化を一層促進する.しかし、Ca−St系
処理剤に対する添加量が0.5%未満では効果はほとん
どない.逆に、その添加量が5%を越えても効果はほと
んど変らないから、処理剤に対する添加量は0.5〜5
%に限定する.
[実施例]
次に、本発明を実施例に基づいて説明する.ロッカーア
ームを鋳造した溶湯の成分(重量%)は次のとおりであ
った.
TC: 3.50
Si: 1.50
Mn: 0.70
Ni: 0.50
Cr:1g.00
Mo: 1.00
W : 5.00
Fe:残部
鋳造時に溶湯処理剤を添加し、鋳造後,所定の焼入れ、
焼戻し処理を施した.使用した溶湯処理剤が、本発明の
範囲に入る実施例は11種類、入らない比較例は2種類
であった.製造したロッカーアームをマーブル液で腐食
して第1図ないし第9図に示す顕微鏡組織写真をとった
.ただし、実施例3、7、9、10の写真は省略した.
第1図ないし第9図の写真は黒色のパーライト基地中に
白色の炭化物の粒が分布することを示している。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an improvement in a method for manufacturing a rocker arm made of high chromium cast iron used in a valve train of an internal combustion engine for an automobile. [Prior art] The method of integrally casting a rocker arm with good Wd wear resistance using high chromium cast iron is disclosed in Japanese Patent Application Laid-Open No. 63-303030.
It is disclosed in the issue. Is the wear resistance of high chromium cast iron rocker arms due to high hardness (Fe, Cr)? This is due to carbides such as C3. [Problem N to be solved by the invention] High hardness Fe-Cr composite compounds tend to precipitate in the form of needles toward the surface layer due to directional solidification. There was a problem in that the acicular carbides facing the surface layer abraded the mating sliding member. Adding tungsten can make the Fe-Cr composite carbide granular (spherical), but in this case, adding a large amount (10% or more) increases the cost, and the high hardness of the tungsten composite carbide makes it difficult to form the other material. This did not solve the problem as it caused wear. The present invention was made to solve the above problems, and its purpose is to manufacture a high chromium cast iron rocker arm that does not cause wear on the mating material. [A Thousand Steps to Solve the Problem] The inventor of the present application believes that the molten metal treatment agent for high chromium cast iron is Fe-Cr.
We discovered that this method is effective in granulating composite carbides, proceeded with our research, and were able to achieve the above objective. The method employed in the present invention is to add 0.3 to 0.6% of a Ca-Si treatment agent to the molten metal in a method of integrally casting a low two car arm using high chromium cast iron. The Cr-St treatment agent contains approximately 30% Ca and approximately 60% Si.
, contains about 10% of impurities, but the Ba.
Sr. Mg, Zr, Ce. Mn. One or more AfLs may be added in an amount of 0.5 to 5% by weight. High chromium cast iron contains 10% or more of Cr, but preferably has a chemical composition of 2.5 to 3.7% by weight;
Si: 1.0-2.0%, Mn: 0.5-1.0%, C
r: L5 ~ 20%, Ni: 0.3 ~ 0.7%,
P: 0.3% or less, S: 1.0% or less, and if necessary, W. Mo, ■, Nb. Ta. Contains a total of 3 to 10% of one or more of Ti and B, with the remainder being F.
[Function] Ca-Si processing agents are used as deoxidizing agents for molten metal, but when used for the purpose of granulation, they If the amount of the treating agent is less than 0.3%, the carbide suppressing effect is insufficient and the purpose of the invention cannot be achieved. Conversely, even if the amount of the treatment agent exceeds 0.6%, the effect will not change and the cost will increase, so the treatment agent for the molten metal should be 0.6%.
.. 3 to 0.6% by weight. Furthermore, Ca-Si-based processing agents have the advantage of good workability and high yields because of their mild reaction. B a, S r, Mg. Zr. C e. Mn and Al have the effect of delaying the fading effect of inoculation, and have a strong affinity with oxygen. Cr
Further promotes carbide granulation. However, if the amount added to the Ca-St-based treatment agent is less than 0.5%, there is almost no effect. On the other hand, even if the amount added exceeds 5%, the effect will hardly change, so the amount added to the processing agent should be 0.5 to 5%.
%. [Example] Next, the present invention will be explained based on an example. The composition (wt%) of the molten metal in which the rocker arm was cast was as follows. TC: 3.50 Si: 1.50 Mn: 0.70 Ni: 0.50 Cr: 1g. 00 Mo: 1.00 W: 5.00 Fe: The remainder was added with a molten metal treatment agent during casting, and after casting, a prescribed quenching,
Tempering treatment was applied. There were 11 examples in which the molten metal treatment agent used fell within the scope of the present invention, and 2 types of comparative examples did not. The manufactured rocker arm was corroded with marble solution and microscopic photographs shown in Figures 1 to 9 were taken. However, the photographs of Examples 3, 7, 9, and 10 were omitted.
The photographs in FIGS. 1 to 9 show that white carbide grains are distributed in a black pearlite matrix.
各写真を画像解析装置にかけ、写真上の炭化物の粒一つ
一つについて、その外接円面積に対する実面積の比率を
測定し、全ての粒の平均値を計算して球状化率とした.
第1表は各実施例及び比較例の溶湯処理,球状化率をま
とめたものである.
(以下余白)
第
1
表
実施例の第1図ないし第7図の写真を比較例の第8図及
び第9図の写真と対比すると、一見して実施例の炭化物
はいずれも丸みのある粒状であるが、比較例の炭化物は
先鋭な針状であることが理解される.このことは,第1
表の球状化率の数値にも明白に表われている.すなわち
、実施例はいずれも球状化率が42%以上と大きいが、
比較例は球状化率が28%、32%と小さくなっている
.40%を越えると、摺動する相手材カムに対する政撃
性が著しく弱まり、相手材カムの摩耗は大幅に減少する
.
[発明の効果]
上記のとおり、木発明の方法は高クロム鋳鉄によるロッ
カーアームを一体鋳造する製造方法において、Ca−S
i系処理剤を0.3〜0.6重量%添加するが、Ca−
Si系処理剤は脱酸作用を有する上に,析出するFe−
Crf化物を球状化させるので、従来の溶湯処理剤を脱
酸剤としてのみ使用していたために析出するFe−Cr
炭化物が針状になる方法に比べる.と、本発明の方法に
より製造したロッカー7−ムは高硬度のFe−Cr炭化
物によって耐摩耗性が従来のものと同様に優れているだ
けでな〈、そのFe−Or炭化物は球状であるから、攻
撃性は薄れ、相手材カムの摩耗は従来のものに比べると
大幅に減少するという優れた効果を奏する.Each photograph was run through an image analysis device, and the ratio of the actual area to the area of the circumscribed circle was measured for each grain of carbide on the photograph, and the average value of all grains was calculated as the spheroidization rate. Table 1 summarizes the molten metal treatment and spheroidization rate of each example and comparative example. (Margin below) Table 1 Comparing the photographs of Figures 1 to 7 of the Examples with the photographs of Figures 8 and 9 of the Comparative Examples, it appears that the carbides of the Examples all have rounded granular shapes. However, it is understood that the carbide in the comparative example has a sharp needle shape. This is the first
This is also clearly seen in the spheroidization rate values in the table. In other words, the spheroidization rate in all of the examples is as high as 42% or more, but
In the comparative examples, the spheroidization rate was small at 28% and 32%. When it exceeds 40%, the impact on the sliding mating cam is significantly weakened, and the wear of the mating cam is greatly reduced. [Effects of the invention] As mentioned above, the method of the wooden invention is a manufacturing method for integrally casting a rocker arm made of high chromium cast iron.
0.3 to 0.6% by weight of i-based treatment agent is added, but Ca-
The Si-based treatment agent not only has a deoxidizing effect but also removes the precipitated Fe-
Since the Crf compound is spheroidized, the Fe-Cr that precipitates when the conventional molten metal treatment agent is used only as a deoxidizing agent is removed.
Compare this to the way carbide becomes needle-like. The rocker 7-m manufactured by the method of the present invention not only has excellent wear resistance due to the high hardness Fe-Cr carbide, but also has excellent wear resistance as the conventional one. , the aggressiveness is reduced, and the wear of the mating cam is significantly reduced compared to conventional ones, which is an excellent effect.
第1図ないし第7図は本発明実施例ロッカーアームの顕
m鏡金属組或写真、
第8図及び第9図は比較例ロッカーアームの顕微鏡金属
組威写真である.Figures 1 to 7 are microscopic metal assembly photographs of rocker arms according to examples of the present invention, and Figures 8 and 9 are microscope metal assembly photographs of comparative example rocker arms.
Claims (1)
する製造方法において、高クロム鋳鉄の溶湯処理として
、Ca−Si処理剤を溶湯に対して0.3〜0.6重量
%添加して粒状の炭化物を析出させることを特徴とする
ロッカーアームの製造方法。 2)Ca−Si処理剤に対してBa、Sr、Mg、Zr
、Ce、Mn、Alの1種又は2種以上を0.5〜5%
重量%添加することを特徴とする請求項1に記載のロッ
カーアームの製造方法。[Claims] 1) In a manufacturing method of integrally casting a rocker arm using high chromium cast iron, as a molten metal treatment of high chromium cast iron, a Ca-Si treatment agent is applied to the molten metal in an amount of 0.3 to 0.6 1. A method for manufacturing a rocker arm, which comprises adding granular carbide by weight % to precipitate granular carbide. 2) Ba, Sr, Mg, Zr for Ca-Si treatment agent
, Ce, Mn, Al or more in an amount of 0.5 to 5%
2. The method for manufacturing a rocker arm according to claim 1, wherein the rocker arm is added in a weight percent.
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1231732A JP2914634B2 (en) | 1989-09-08 | 1989-09-08 | Rocker arm manufacturing method |
EP19900116371 EP0416418B1 (en) | 1989-09-08 | 1990-08-27 | Method of making rocker arm |
DE1990629074 DE69029074T2 (en) | 1989-09-08 | 1990-08-27 | Method of making rocker arms |
US07/821,908 US5195473A (en) | 1989-09-08 | 1992-01-15 | Rocker arm and method of casting |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1231732A JP2914634B2 (en) | 1989-09-08 | 1989-09-08 | Rocker arm manufacturing method |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0397828A true JPH0397828A (en) | 1991-04-23 |
JP2914634B2 JP2914634B2 (en) | 1999-07-05 |
Family
ID=16928167
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP1231732A Expired - Fee Related JP2914634B2 (en) | 1989-09-08 | 1989-09-08 | Rocker arm manufacturing method |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0416418B1 (en) |
JP (1) | JP2914634B2 (en) |
DE (1) | DE69029074T2 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104087813B (en) * | 2014-06-19 | 2016-01-27 | 宁国市正兴耐磨材料有限公司 | The extraordinary special mill ball in a kind of mine |
CN109723513A (en) * | 2017-10-30 | 2019-05-07 | 丹阳市金长汽车部件有限公司 | A kind of engine valve rocker arm |
CN108220760B (en) * | 2017-12-29 | 2021-05-14 | 中钢集团邢台机械轧辊有限公司 | Nb-containing high-chromium iron roller |
CN112695242B (en) * | 2020-11-30 | 2023-05-05 | 中钢集团邢台机械轧辊有限公司 | Cogging roll and preparation method thereof |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4869718A (en) * | 1971-12-24 | 1973-09-21 | ||
JPS63303030A (en) * | 1987-05-30 | 1988-12-09 | Nippon Piston Ring Co Ltd | Locker arm |
JPH01159352A (en) * | 1987-09-08 | 1989-06-22 | Honda Motor Co Ltd | Combination of sliding member |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2045414C3 (en) * | 1970-09-15 | 1975-06-05 | Koerver & Nehring Gmbh, 4150 Krefeld | Use of an austenitic cast iron with lamellar graph for plain bearings, etc. |
JPS5911656B2 (en) * | 1976-06-24 | 1984-03-16 | 川崎重工業株式会社 | High hardness wear-resistant cast iron |
US4094666A (en) * | 1977-05-24 | 1978-06-13 | Metal Research Corporation | Method for refining molten iron and steels |
DD254217A1 (en) * | 1982-08-02 | 1988-02-17 | Juergen Jahn | METHOD FOR THE PRODUCTION OF HIGH-WEAR, IMPACT-RESISTANT CASTING PARTS |
-
1989
- 1989-09-08 JP JP1231732A patent/JP2914634B2/en not_active Expired - Fee Related
-
1990
- 1990-08-27 DE DE1990629074 patent/DE69029074T2/en not_active Expired - Fee Related
- 1990-08-27 EP EP19900116371 patent/EP0416418B1/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4869718A (en) * | 1971-12-24 | 1973-09-21 | ||
JPS63303030A (en) * | 1987-05-30 | 1988-12-09 | Nippon Piston Ring Co Ltd | Locker arm |
JPH01159352A (en) * | 1987-09-08 | 1989-06-22 | Honda Motor Co Ltd | Combination of sliding member |
Also Published As
Publication number | Publication date |
---|---|
DE69029074D1 (en) | 1996-12-12 |
JP2914634B2 (en) | 1999-07-05 |
EP0416418B1 (en) | 1996-11-06 |
DE69029074T2 (en) | 1997-04-03 |
EP0416418A2 (en) | 1991-03-13 |
EP0416418A3 (en) | 1992-06-10 |
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